A. Malamitsipuchner et al., ENDOTHELIN-1-21 PLASMA-LEVELS IN FETUSES AT 18-24 WEEKS OF GESTATION, Journal of perinatal medicine, 23(4), 1995, pp. 321-325
This study aimed to establish normal endothelin (ET) ranges in non mal
formed appropriate for gestational age fetuses of 18-24 weeks gestatio
n and to investigate a possible correlation between maternal and fetal
ET plasma levels. Twenty ''mother-fetus'' pairs were included in the
study. The determination of ET 1-21 was performed by radioimmunoassay
using 1 ml of fetal blood obtained by cordocentesis - indicated for va
rious reasons - and in 2 ml of maternal venous blood. The statistical
analysis involved the Wilcoxon test for pair differences and the Spear
man rank correlation coefficient. Fetal and maternal ET 1-21 levels we
re respectively 11.39 +/- 2.22 pmol/L and 6.44 +/- 1.00 pmol/L. Fetal
levels were significantly higher (p < 0.01) thus excluding passive ET
transfer through the placenta, while no correlation between maternal a
nd fetal levels was found. It is speculated that high fetal ET 1-21 le
vels result from increased ET production, which possess cell prolifera
tive properties and/or decreased ET removal from the fetal circulation
because of hypofunctioning lungs and kidneys. It can be assumed that
the increased amounts of fetal ETs contribute to normal growth and dev
elopment directly as well as by regulating vascular tonus and local bl
ood flow.